Improvement in tappet-clamps for stamp-stems



N. J. COLMAN. TAPPET-CLAMP S FOR STAMP-STEMS. N@. 17o,zae.

Patented Nov. 23,1875;

It RTEIS, momurmomm Unrrnn STATES NICHOLAS J. OOLMAN, or SAN FRANCISCO, CALIFORNIA.

PATENT OF I-on. I

IMPROVEMENT IN TAPPET-CLAMPSFOR STAMP-STEMS.

Specification forming part of Letters PatentNo. 170,236, dated November 23, 1875; application filed September 23, 1875.

To all whom it may concern:

Be it known that I, NICHOLAS J. CoLMAN, of San Francisco city and county, State of California, have invented an Improved Tappet-(llamp for Stamp-Stems; and I do hereby declare the following description and accompanying drawings are sufficient to enable any person skilled in the art or science-to which it most nearly appertains to make and use my said invention or improvement, without further invention or experiment.

The object of my invention is to provide an improved device for -securing tappets to the stamp-stems of quartz-mills, so that when working they will not become loosened or slip upon the stem.

The position of the tappet on the stampstems of quartz-mills must be changed occasionally as the stamp wears away. It is necessary, therefore, to provide a clamping device which will secure the tappet at any point on the stem; and, as the stem is made cylindrical and with a smooth surface, much difficulty has heretofore been encountered in keeping the tappet in place, as the repeated lifting upon it by the cam and the jar of the drop of the stamp tend to loosen it, thus causing much annoyance and waste of time, as the mill must be stopped in order to I fasten it again.

My invention is intended to remedy this difficulty by supplying a clamp which cannot become loosened by either of the causes above mentioned.

,Beferring to the accompanying drawings let A represent the stamp-stem, and B the A will only be necessary to remove the wedge tappet. In the construction of this tappet I form. two narrow boxes or enlargements, c c, on one side of the tappet, inside of the flanges. These boxes are in the same line, and a small space is leftbetween their inner ends. Inside of each box aninclined groove is made, which communicates with the bore of the tappet. The upper face of each groove inclines from the inner end of the box toward the end of the tappet, thus giving two oppositely- Each of the keys or gibs D have only one inclined face, while the opposite or straight face is made convex, to fit the convexity of thev stamp-stem. These gibs or keys are introduced into the recesses of the boxes 0 0 before the tappet is placed upon the stem, and as fixed point the gibs D are forced apart by awedge or key, F, driven in between them trans- 1 versely to the ends of the boxes, so as to tighten them upon the stem, the inclined face of the box and key serving to clamp the gibs upon the stem, according to the force with which.

clamp the tappets to the stem. By this arrangement, when the cam strikes the tappet to lift the stamp, the tendency is to drive the tappet upward, consequently tightening it up-.

on the lower gib D, while the downward jar of the stamp will tighten it upon the upper gib, thus securing the immovability of the tappet from its keyed position on the stem. I

thus secure a large clamping-surface, as the gibs D D will bear upon the stem along the greater portion of the length of the tapp'et, and their gripe will be proportionately increased.

When it is desired to'move the tappet, it

or key F, when a tap upon the gibs D with a hammer will loosen them so thatthe tappet can be moved up or down, as desired.

I thus provide a'very effective, cheap, and convenient tappet-clamp, which cannot be shifted by the action of the cam, and which will, therefore, be a great improvement on stamp-mills.

Having thus described my invention, what I claim, anddesire to secure by Letters Patent is 1: The tappet A, having the boxes B'B, with their inclined grooves or chambers, in combination with the corresponding gibs D 9 I 179.236 i i and the wedge or key F, substantially as and tions, so as to tighten them upon the stem by for the purpose above described. i a'wedge or key,F, driven tinbetweenjtliemQ 2. Animproved tappet-clainp,consisting of substantially as above specified. i i 1 i g the tappet A5p10videdwith twobppositely- NICHOLAS J. OOLMAN. s Q 1 i inclined chajmbers, on each of which a taper- Witnesses: it 3 ing wedge or gib, D, is placed, and the two GEO. H. STRONG, Wedges orgibsD are forced in Opposite direc- J NO. L. BOONE. 

